Mahmoud Drif - Academia.edu (original) (raw)

Papers by Mahmoud Drif

2012 24th International Conference on Microelectronics (ICM), 2012

ABSTRACT Recent advances in control algorithms embedded into a Field Programmable Gate Array (FPG... more ABSTRACT Recent advances in control algorithms embedded into a Field Programmable Gate Array (FPGA) allowed the application of such algorithms in real engineering problems (robotic, image and signal processing, control, power electronics, etc.), however, the application of such technologies in the solar energy field is very limited. The embedded advanced algorithm into FPGA can play a very important role in renewable energy systems for control, monitoring, supervision, etc. FPGA technology was employed due to its development, flexibility and low cost. In this paper, the incremental conductance (IncCond) algorithm is implemented on FPGA for tracking the Maximum Power Point (MPP) of a photovoltaic (PV) array. The IncCond algorithm has been designed using a description language (VHSIC standing for very-high-speed integrated circuits) then implemented on Xilinx Virtex-II-Pro(xc2v1000-4fg456. Modelsim-based simulation results confirm the good tracking efficiency (96%) and rapid response time (2ms). It has been confirmed that the implemented algorithm performs better than the well known Perturb and Observe (P&O) algorithm.

Power Electronics and Drives

In this paper, a three-phase shunt active power filter (SAPF) controller with a fully digital imp... more In this paper, a three-phase shunt active power filter (SAPF) controller with a fully digital implementation is presented. The main goal of this contribution is to implement a digital direct power control (DDPC) algorithm without phase-locked-loop (PLL) for SAPF. This algorithm is intended for power quality improvement and current harmonic elimination. The controller introduced in this paper is cost-effective, has a fast-dynamic response, and has a simple hardware implementation. In order to comply with the above specifications, a dedicated controller has been conceived and fully implemented within a field-programmable gate array (FPGA) device. This FPGA-based controller integrates the whole signal-processing functions needed to drive the SAPF, as well as an original method for sector identification. The intended controller provides the desired power references to select the optimal switching sequences. The switching orders follow the grid reference to drive the voltage source inver...

-Dans cette étude, nous avons montré que le critère de solubilité du monomère dans le cristal liq... more -Dans cette étude, nous avons montré que le critère de solubilité du monomère dans le cristal liquide est bien rempli. De plus, le caractère mésomorphe du monomère lui confère la capacité de s'orienter dans le milieu cristal liquide, ce qui est très important pour la formation d'un réseau polymère anisotrope. L'étude des propriétés ferroélectriques et électro-optiques des gels nous a permis de mettre en évidence que le réseau polymère anisotrope formé en phase SmC* joue un rôle stabilisateur de la structure en hélice de la phase hélioélectrique. Ce réseau anisotrope dispersé dans le volume au sein de la cellule cristal liquide permet le contrôle de la réorientation sous champ électrique du cristal liquide. Nous avons montré que cet effet du réseau est intimement lié à sa structure fibrillaire et anisotrope interagissant fortement avec le cristal liquide, grâce à des forces d'ancrage et élastique. Abstract-Monomer solubility is identified as the primary factor determining network morphology in polymer stabilized ferroelectric liquid crystal textures. The phase diagrams of monomer and polymer/liquid crystal (LC) mixtures are established by both polarized optical microscopy and differential scanning calorimetry. This study show that the polymer network formed in liquid crystal is fibrilar and anisotropic. Additionally, the optical and the electro optic properties are reported for all studied polymer concentrations.

2022 International Conference of Advanced Technology in Electronic and Electrical Engineering (ICATEEE)

International Journal of Energy Optimization and Engineering

To ensure the safe and stable operation of solar photovoltaic system-based power systems, it is e... more To ensure the safe and stable operation of solar photovoltaic system-based power systems, it is essential to predict the PV module output performance under varying operating conditions. In this paper, the interest is to develop an accurate model of a PV module in order to predict its electrical characteristics. For this purpose, an artificial neural network (ANN) based on the backpropagation algorithm is proposed for the performance prediction of a photovoltaic module. In this modeling approach, the temperature and illumination are taken as inputs and the current of the mathematical model as output for the learning of the ANN-PV-Panel. Simulation results showing the performance of the ANN model in obtaining the electrical properties of the chosen PV panel, including I–V curves and P–V curves, in comparison with the mathematical model performance are presented and discussed. The given results show that the error of the maximum power is very small while the current error is about 10-8...

Journal of New Materials for Electrochemical Systems

Ca1-xSrxMnO3 (x = 0, 0.1, 0.2) nanoparticules were synthesized by the co- precipitation method. T... more Ca1-xSrxMnO3 (x = 0, 0.1, 0.2) nanoparticules were synthesized by the co- precipitation method. The structural analysis reveals the presence of Octahedral coordination of MnO4. Fourier transform infrared spectroscopy (FTIR) spectra of MnO4 show the occurrence of O-Mn-O vibrational mode at around 590 cm-1. The XRD indicates that the samples are Rhombohedral lattice. The differential and thermo gravimetric analysis, curve obtained from the composition x=0.1,it has distinct pure phase at 600°C. The study of electrochemical behavior was carried out by cyclic Voltammetry (CV) and impedance spectroscopy (EIS).Show that the apparent electrochemical activity improves by increasing the strontium concentration. This is due to the particle size effect of strontium.

Optik, 2021

Abstract This paper presents a novel circuit-based model of photovoltaic (PV) source (cell, modul... more Abstract This paper presents a novel circuit-based model of photovoltaic (PV) source (cell, module or array) that can be easily integrated into any circuit-oriented simulators such as PSpice, PSCAD/EMTDC, PSIM, PowerSys of MATLAB/Simulink, etc. This proposed model is able to simulate accurately any commercial PV module behavior either exposed to uniform or non-uniform irradiance distributions. Moreover, it can also simulate perfectly PV arrays behavior in large scale PV systems. It is mainly derived from the conventional one-diode equivalent circuit model, which consists of a current source, a diode and two resistors. By modifying the linear part of this latter and including implicitly the effect of weather parameters (irradiance and cell temperature) on the circuit elements, our proposed model will encompass two types of dependent sources (voltage and current sources) and two resistances. To validate the truthfulness of the proposed novel model, comparisons between simulated and outdoor measured I-V characteristics on commercial PV module are done. Preliminary results have shown promising outputs and accuracy of this model.

Lecture Notes in Computer Science, 2012

ABSTRACT This paper addresses the feature subset selection for an automatic Arabic speaker recogn... more ABSTRACT This paper addresses the feature subset selection for an automatic Arabic speaker recognition system. An effective algorithm based on genetic algorithm is proposed for discovering the best feature combinations using feature reduction and recognition error rate as performance measure. Experimentation is carried out using QSDAS corpora. The results of experiments indicate that, with the optimized feature subset, the performance of the system is improved. Moreover, the speed of recognition is significantly increased, number of features is reduced over 60% which consequently decrease the complexity of our ASR system

2011 11th International Conference on Hybrid Intelligent Systems (HIS), 2011

In the last years, face verification has gained a great interest in the pattern recognition commu... more In the last years, face verification has gained a great interest in the pattern recognition community and in many application fields. It is among the most attractive research areas because face images can be captured in a non-intrusive way. Many algorithms have been developed in this area, among them the Principal Component Analysis (PCA) is a typical face based technique

2011 11th International Conference on Hybrid Intelligent Systems (HIS), 2011

Feature Selection is an important task which can affect the performance of pattern classification... more Feature Selection is an important task which can affect the performance of pattern classification and recognition. In this paper, we present a feature selection algorithm based on genetic algorithm optimization. The algorithm adopts classifier performance and the number of the selected features as heuristic information, and selects the optimal feature subset in terms of feature set size and classification performance.

ABSTRACT La Universidad de Jaén, consciente de la evolución ascendente de las instalaciones de si... more ABSTRACT La Universidad de Jaén, consciente de la evolución ascendente de las instalaciones de sistemas fotovoltaicos conectados a la red, junto al afán de identificar a la universidad con las fuentes de energías respetuosas con el medio ambiente e implicar a la comunidad universitaria en el desarrollo y uso de energías renovables, ha apostado por la energía fotovoltáica conectada a la red. Esta apuesta se ha materializado con la instalación de 200 kWp conectados a la red, en lo que se conoce como Proyecto UNIVER (UNIversidad VERde).

Renewable Energy, 2008

A new method for estimating the irradiance on a partially shaded photovoltaic generator system is... more A new method for estimating the irradiance on a partially shaded photovoltaic generator system is proposed. The basic principle of this method consists of two parts: firstly, an approximation of the obstacles' outline or the local horizon by a set of linear functions. Here, a survey of the surroundings is based on the reading of the topographic coordinates of the only significant points of all the objects surrounding the photovoltaic generator. Secondly, the irradiance on the photovoltaic plane is estimated using an accurate model such as the Perez et al. model and assuming that the shading affects both the direct radiation and a part of the diffuse component (circumsolar component). The aim of this paper is to present the principles of the proposed method and the algorithm used for calculating the irradiance on shaded planes. In addition, the results of the comparison between the simulated and measured values of this method are presented.

Revue des Energies Renouvelables, 2010

In this paper, an application of an Evolving Polynomial Neural Network (EPNN) for prediction of m... more In this paper, an application of an Evolving Polynomial Neural Network (EPNN) for prediction of meteorological time series (global solar irradiation, air temperature, relative humidity, and wind speed) is described. Prediction of such data plays a very important role in design of the renewable energy systems. The problem of time series prediction is formulated as a system identification problem, where the input of the system is the past values (y (t-1), y (t-2), y (t-3), …) of a time series and its desired output (y (t), y (t + 1), y (t + 2), …) are the future of a time series. In this study, a dataset of meteorological time series for five years collected in Algiers (Algeria) by the National Office of Meteorology has been used. The obtained results showed a good agreement between both series, measured and predicted. The correlation coefficient (r) is arranged between 0.9821 and 0.9923, the mean relative error over the whole data set is not exceed 15.4 %. The proposed model provides more accurate results than other ANN's architecture, wavenet (wavelet-network) and Adaptive Neuro-Fuzzy Inference Scheme (ANFIS). In order to show the effectiveness of the proposed predictor, the predicted data have been used for sizing, and prediction of the output energy of photovoltaic systems. Résumé-Dans cet article, une application sur un réseau neural polynomial en constante évolution (EPNN) pour la prédiction de séries temporelles météorologiques (rayonnement solaire global, température de l'air, humidité relative et vitesse du vent) est décrite. La prévision de ces données joue un rôle important dans la conception des systèmes d'énergie renouvelable. Le problème de la prédiction de séries temporelles est formulé comme un problème d'identification du système, où l'entrée du système est les valeurs du passé (y (t-1), y (t-2), y (t-3), ...) des séries chronologiques et sa sortie désirée (y (t), y (t + 1), y (t + 2), ...) sont l'avenir d'une série chronologique. Dans cette étude, un ensemble de données de séries chronologiques météorologiques recueillies pendant cinq ans à Alger (Algérie) par l'Office National de Météorologie a été utilisé. Les résultats obtenus montrent un bon accord entre les deux séries, mesurées et prédites. Le coefficient de corrélation (r) est disposé entre 0,9821 et 0,9923, et l'erreur relative moyenne sur l'ensemble des données n'est pas excéder 15,4 %. Le modèle proposé fournit des résultats plus précis que dans d'autres techniques 'Ann's', wavenet (réseau d'ondelettes) et Adaptive Neuro-Fuzzy Inference Scheme (ANFIS). Afin de démontrer l'efficacité de l'indicateur proposé, les données prédites ont été utilisées pour le calibrage, et la prédiction de l'énergie de sortie de systèmes photovoltaïques.

Résumé − L'objet de ce papier est de présenter le concept et la théorie d'une nouvelle ap... more Résumé − L'objet de ce papier est de présenter le concept et la théorie d'une nouvelle approche de commande non linéaire pour un convertisseur cc/cc dévolteur (Buk Converter) connecté à une charge. Les résultats des études de simulation et de l'expérimentation de ce système électronique sont également présentés. Le principe de base de la technique consiste en l'asservissement en un seul cycle de commutation de la tension d'entrée (par exemple: tension d'un générateur photovoltaïque -GPV-) du convertisseur à une valeur de consigne de nature fixe ou variable (par exemple: tension correspondant au point de puissance maximale -PPM-du GPV). Après avoir effectuée la synthèse de cette technique, une étude de simulation de ce système, utilisant le logiciel de simulation dynamique Matlab/Simulink™ a été réalisée. Afin de valider cette dernière, un appareil de commande a été mis au point et expérimenté. Abstract − The purpose of this paper is to present the concept and...

Journal Européen des Systèmes Automatisés

This paper proposes a generalized technique to minimize power losses of PV arrays connected in To... more This paper proposes a generalized technique to minimize power losses of PV arrays connected in Total Cross-Tied (TCT), under both current and voltage mismatch effects. The proposed method is based on the classification of the electrical data of the PV modules composing the photovoltaic array in order to identify the mismatch type, then applying an arrangement of the PV modules according to the mismatch type found. The design process of the proposed algorithm is detailed and its validity and performance are verified under different mismatch scenarios. The efficiency enhancement is verified for different mismaths cases and the computed results reveal that the proposed algorithm can achieve an improvement of around 30% in the PV array power. Furthermore, a comparative study with SuDoKu and genetic algorithms are performed. The obtained results under MATLAB/Simulink software highlighted the superiority of the proposed method in comparison to the compared ones. The enhancement resides in the implementation simplicity as well as in the minimization of the number of infection points indicating smooth I-V and P-V characteristic curves.

ABSTRACT In this paper, a comprehensive method for evaluating energy losses of a grid-connected b... more ABSTRACT In this paper, a comprehensive method for evaluating energy losses of a grid-connected building integrated photovoltaic (GC-BIPV) system due to partial shading is described. The method consists to make a comparison between theoretical and measured (monitoring data) curves of the maximum output energy produced by a GC-BIPV system installed at Jaén University (Spain). The results showed that loss of energy is 1.79 kWh/day, which corresponds to a shading factor of 14.4%.

International Multi-Conference on Systems, Signals and Devices, SSD 2012 - Summary Proceedings, 2012

This paper presents a simplified method for evaluating the energy loss involved in a grid connect... more This paper presents a simplified method for evaluating the energy loss involved in a grid connected building integrated photovoltaic (GC-BIPV) system due to partial shading. The method consists in the comparison of the monthly theoretical curve (for un-shaded PV generator) and real fitted curve (deducted from monitoring data) of the maximum energy produced by the PV generator.

This paper deals with developing automatic classification algorithms for identifying images of F-... more This paper deals with developing automatic classification algorithms for identifying images of F-actin distribution in endothelial cells with different treatment of drugs. A novel combination of genetic algorithm based feature selection, used to obtain an optimal feature set, and artificial neural network methods including the multilayer feedforward network and the functional link network was used in the classification. q 1997 Elsevier Science B.V.

2012 24th International Conference on Microelectronics (ICM), 2012

ABSTRACT Recent advances in control algorithms embedded into a Field Programmable Gate Array (FPG... more ABSTRACT Recent advances in control algorithms embedded into a Field Programmable Gate Array (FPGA) allowed the application of such algorithms in real engineering problems (robotic, image and signal processing, control, power electronics, etc.), however, the application of such technologies in the solar energy field is very limited. The embedded advanced algorithm into FPGA can play a very important role in renewable energy systems for control, monitoring, supervision, etc. FPGA technology was employed due to its development, flexibility and low cost. In this paper, the incremental conductance (IncCond) algorithm is implemented on FPGA for tracking the Maximum Power Point (MPP) of a photovoltaic (PV) array. The IncCond algorithm has been designed using a description language (VHSIC standing for very-high-speed integrated circuits) then implemented on Xilinx Virtex-II-Pro(xc2v1000-4fg456. Modelsim-based simulation results confirm the good tracking efficiency (96%) and rapid response time (2ms). It has been confirmed that the implemented algorithm performs better than the well known Perturb and Observe (P&O) algorithm.

Power Electronics and Drives

In this paper, a three-phase shunt active power filter (SAPF) controller with a fully digital imp... more In this paper, a three-phase shunt active power filter (SAPF) controller with a fully digital implementation is presented. The main goal of this contribution is to implement a digital direct power control (DDPC) algorithm without phase-locked-loop (PLL) for SAPF. This algorithm is intended for power quality improvement and current harmonic elimination. The controller introduced in this paper is cost-effective, has a fast-dynamic response, and has a simple hardware implementation. In order to comply with the above specifications, a dedicated controller has been conceived and fully implemented within a field-programmable gate array (FPGA) device. This FPGA-based controller integrates the whole signal-processing functions needed to drive the SAPF, as well as an original method for sector identification. The intended controller provides the desired power references to select the optimal switching sequences. The switching orders follow the grid reference to drive the voltage source inver...

-Dans cette étude, nous avons montré que le critère de solubilité du monomère dans le cristal liq... more -Dans cette étude, nous avons montré que le critère de solubilité du monomère dans le cristal liquide est bien rempli. De plus, le caractère mésomorphe du monomère lui confère la capacité de s'orienter dans le milieu cristal liquide, ce qui est très important pour la formation d'un réseau polymère anisotrope. L'étude des propriétés ferroélectriques et électro-optiques des gels nous a permis de mettre en évidence que le réseau polymère anisotrope formé en phase SmC* joue un rôle stabilisateur de la structure en hélice de la phase hélioélectrique. Ce réseau anisotrope dispersé dans le volume au sein de la cellule cristal liquide permet le contrôle de la réorientation sous champ électrique du cristal liquide. Nous avons montré que cet effet du réseau est intimement lié à sa structure fibrillaire et anisotrope interagissant fortement avec le cristal liquide, grâce à des forces d'ancrage et élastique. Abstract-Monomer solubility is identified as the primary factor determining network morphology in polymer stabilized ferroelectric liquid crystal textures. The phase diagrams of monomer and polymer/liquid crystal (LC) mixtures are established by both polarized optical microscopy and differential scanning calorimetry. This study show that the polymer network formed in liquid crystal is fibrilar and anisotropic. Additionally, the optical and the electro optic properties are reported for all studied polymer concentrations.

2022 International Conference of Advanced Technology in Electronic and Electrical Engineering (ICATEEE)

International Journal of Energy Optimization and Engineering

To ensure the safe and stable operation of solar photovoltaic system-based power systems, it is e... more To ensure the safe and stable operation of solar photovoltaic system-based power systems, it is essential to predict the PV module output performance under varying operating conditions. In this paper, the interest is to develop an accurate model of a PV module in order to predict its electrical characteristics. For this purpose, an artificial neural network (ANN) based on the backpropagation algorithm is proposed for the performance prediction of a photovoltaic module. In this modeling approach, the temperature and illumination are taken as inputs and the current of the mathematical model as output for the learning of the ANN-PV-Panel. Simulation results showing the performance of the ANN model in obtaining the electrical properties of the chosen PV panel, including I–V curves and P–V curves, in comparison with the mathematical model performance are presented and discussed. The given results show that the error of the maximum power is very small while the current error is about 10-8...

Journal of New Materials for Electrochemical Systems

Ca1-xSrxMnO3 (x = 0, 0.1, 0.2) nanoparticules were synthesized by the co- precipitation method. T... more Ca1-xSrxMnO3 (x = 0, 0.1, 0.2) nanoparticules were synthesized by the co- precipitation method. The structural analysis reveals the presence of Octahedral coordination of MnO4. Fourier transform infrared spectroscopy (FTIR) spectra of MnO4 show the occurrence of O-Mn-O vibrational mode at around 590 cm-1. The XRD indicates that the samples are Rhombohedral lattice. The differential and thermo gravimetric analysis, curve obtained from the composition x=0.1,it has distinct pure phase at 600°C. The study of electrochemical behavior was carried out by cyclic Voltammetry (CV) and impedance spectroscopy (EIS).Show that the apparent electrochemical activity improves by increasing the strontium concentration. This is due to the particle size effect of strontium.

Optik, 2021

Abstract This paper presents a novel circuit-based model of photovoltaic (PV) source (cell, modul... more Abstract This paper presents a novel circuit-based model of photovoltaic (PV) source (cell, module or array) that can be easily integrated into any circuit-oriented simulators such as PSpice, PSCAD/EMTDC, PSIM, PowerSys of MATLAB/Simulink, etc. This proposed model is able to simulate accurately any commercial PV module behavior either exposed to uniform or non-uniform irradiance distributions. Moreover, it can also simulate perfectly PV arrays behavior in large scale PV systems. It is mainly derived from the conventional one-diode equivalent circuit model, which consists of a current source, a diode and two resistors. By modifying the linear part of this latter and including implicitly the effect of weather parameters (irradiance and cell temperature) on the circuit elements, our proposed model will encompass two types of dependent sources (voltage and current sources) and two resistances. To validate the truthfulness of the proposed novel model, comparisons between simulated and outdoor measured I-V characteristics on commercial PV module are done. Preliminary results have shown promising outputs and accuracy of this model.

Lecture Notes in Computer Science, 2012

ABSTRACT This paper addresses the feature subset selection for an automatic Arabic speaker recogn... more ABSTRACT This paper addresses the feature subset selection for an automatic Arabic speaker recognition system. An effective algorithm based on genetic algorithm is proposed for discovering the best feature combinations using feature reduction and recognition error rate as performance measure. Experimentation is carried out using QSDAS corpora. The results of experiments indicate that, with the optimized feature subset, the performance of the system is improved. Moreover, the speed of recognition is significantly increased, number of features is reduced over 60% which consequently decrease the complexity of our ASR system

2011 11th International Conference on Hybrid Intelligent Systems (HIS), 2011

In the last years, face verification has gained a great interest in the pattern recognition commu... more In the last years, face verification has gained a great interest in the pattern recognition community and in many application fields. It is among the most attractive research areas because face images can be captured in a non-intrusive way. Many algorithms have been developed in this area, among them the Principal Component Analysis (PCA) is a typical face based technique

2011 11th International Conference on Hybrid Intelligent Systems (HIS), 2011

Feature Selection is an important task which can affect the performance of pattern classification... more Feature Selection is an important task which can affect the performance of pattern classification and recognition. In this paper, we present a feature selection algorithm based on genetic algorithm optimization. The algorithm adopts classifier performance and the number of the selected features as heuristic information, and selects the optimal feature subset in terms of feature set size and classification performance.

ABSTRACT La Universidad de Jaén, consciente de la evolución ascendente de las instalaciones de si... more ABSTRACT La Universidad de Jaén, consciente de la evolución ascendente de las instalaciones de sistemas fotovoltaicos conectados a la red, junto al afán de identificar a la universidad con las fuentes de energías respetuosas con el medio ambiente e implicar a la comunidad universitaria en el desarrollo y uso de energías renovables, ha apostado por la energía fotovoltáica conectada a la red. Esta apuesta se ha materializado con la instalación de 200 kWp conectados a la red, en lo que se conoce como Proyecto UNIVER (UNIversidad VERde).

Renewable Energy, 2008

A new method for estimating the irradiance on a partially shaded photovoltaic generator system is... more A new method for estimating the irradiance on a partially shaded photovoltaic generator system is proposed. The basic principle of this method consists of two parts: firstly, an approximation of the obstacles' outline or the local horizon by a set of linear functions. Here, a survey of the surroundings is based on the reading of the topographic coordinates of the only significant points of all the objects surrounding the photovoltaic generator. Secondly, the irradiance on the photovoltaic plane is estimated using an accurate model such as the Perez et al. model and assuming that the shading affects both the direct radiation and a part of the diffuse component (circumsolar component). The aim of this paper is to present the principles of the proposed method and the algorithm used for calculating the irradiance on shaded planes. In addition, the results of the comparison between the simulated and measured values of this method are presented.

Revue des Energies Renouvelables, 2010

In this paper, an application of an Evolving Polynomial Neural Network (EPNN) for prediction of m... more In this paper, an application of an Evolving Polynomial Neural Network (EPNN) for prediction of meteorological time series (global solar irradiation, air temperature, relative humidity, and wind speed) is described. Prediction of such data plays a very important role in design of the renewable energy systems. The problem of time series prediction is formulated as a system identification problem, where the input of the system is the past values (y (t-1), y (t-2), y (t-3), …) of a time series and its desired output (y (t), y (t + 1), y (t + 2), …) are the future of a time series. In this study, a dataset of meteorological time series for five years collected in Algiers (Algeria) by the National Office of Meteorology has been used. The obtained results showed a good agreement between both series, measured and predicted. The correlation coefficient (r) is arranged between 0.9821 and 0.9923, the mean relative error over the whole data set is not exceed 15.4 %. The proposed model provides more accurate results than other ANN's architecture, wavenet (wavelet-network) and Adaptive Neuro-Fuzzy Inference Scheme (ANFIS). In order to show the effectiveness of the proposed predictor, the predicted data have been used for sizing, and prediction of the output energy of photovoltaic systems. Résumé-Dans cet article, une application sur un réseau neural polynomial en constante évolution (EPNN) pour la prédiction de séries temporelles météorologiques (rayonnement solaire global, température de l'air, humidité relative et vitesse du vent) est décrite. La prévision de ces données joue un rôle important dans la conception des systèmes d'énergie renouvelable. Le problème de la prédiction de séries temporelles est formulé comme un problème d'identification du système, où l'entrée du système est les valeurs du passé (y (t-1), y (t-2), y (t-3), ...) des séries chronologiques et sa sortie désirée (y (t), y (t + 1), y (t + 2), ...) sont l'avenir d'une série chronologique. Dans cette étude, un ensemble de données de séries chronologiques météorologiques recueillies pendant cinq ans à Alger (Algérie) par l'Office National de Météorologie a été utilisé. Les résultats obtenus montrent un bon accord entre les deux séries, mesurées et prédites. Le coefficient de corrélation (r) est disposé entre 0,9821 et 0,9923, et l'erreur relative moyenne sur l'ensemble des données n'est pas excéder 15,4 %. Le modèle proposé fournit des résultats plus précis que dans d'autres techniques 'Ann's', wavenet (réseau d'ondelettes) et Adaptive Neuro-Fuzzy Inference Scheme (ANFIS). Afin de démontrer l'efficacité de l'indicateur proposé, les données prédites ont été utilisées pour le calibrage, et la prédiction de l'énergie de sortie de systèmes photovoltaïques.

Résumé − L'objet de ce papier est de présenter le concept et la théorie d'une nouvelle ap... more Résumé − L'objet de ce papier est de présenter le concept et la théorie d'une nouvelle approche de commande non linéaire pour un convertisseur cc/cc dévolteur (Buk Converter) connecté à une charge. Les résultats des études de simulation et de l'expérimentation de ce système électronique sont également présentés. Le principe de base de la technique consiste en l'asservissement en un seul cycle de commutation de la tension d'entrée (par exemple: tension d'un générateur photovoltaïque -GPV-) du convertisseur à une valeur de consigne de nature fixe ou variable (par exemple: tension correspondant au point de puissance maximale -PPM-du GPV). Après avoir effectuée la synthèse de cette technique, une étude de simulation de ce système, utilisant le logiciel de simulation dynamique Matlab/Simulink™ a été réalisée. Afin de valider cette dernière, un appareil de commande a été mis au point et expérimenté. Abstract − The purpose of this paper is to present the concept and...

Journal Européen des Systèmes Automatisés

This paper proposes a generalized technique to minimize power losses of PV arrays connected in To... more This paper proposes a generalized technique to minimize power losses of PV arrays connected in Total Cross-Tied (TCT), under both current and voltage mismatch effects. The proposed method is based on the classification of the electrical data of the PV modules composing the photovoltaic array in order to identify the mismatch type, then applying an arrangement of the PV modules according to the mismatch type found. The design process of the proposed algorithm is detailed and its validity and performance are verified under different mismatch scenarios. The efficiency enhancement is verified for different mismaths cases and the computed results reveal that the proposed algorithm can achieve an improvement of around 30% in the PV array power. Furthermore, a comparative study with SuDoKu and genetic algorithms are performed. The obtained results under MATLAB/Simulink software highlighted the superiority of the proposed method in comparison to the compared ones. The enhancement resides in the implementation simplicity as well as in the minimization of the number of infection points indicating smooth I-V and P-V characteristic curves.

ABSTRACT In this paper, a comprehensive method for evaluating energy losses of a grid-connected b... more ABSTRACT In this paper, a comprehensive method for evaluating energy losses of a grid-connected building integrated photovoltaic (GC-BIPV) system due to partial shading is described. The method consists to make a comparison between theoretical and measured (monitoring data) curves of the maximum output energy produced by a GC-BIPV system installed at Jaén University (Spain). The results showed that loss of energy is 1.79 kWh/day, which corresponds to a shading factor of 14.4%.

International Multi-Conference on Systems, Signals and Devices, SSD 2012 - Summary Proceedings, 2012

This paper presents a simplified method for evaluating the energy loss involved in a grid connect... more This paper presents a simplified method for evaluating the energy loss involved in a grid connected building integrated photovoltaic (GC-BIPV) system due to partial shading. The method consists in the comparison of the monthly theoretical curve (for un-shaded PV generator) and real fitted curve (deducted from monitoring data) of the maximum energy produced by the PV generator.

This paper deals with developing automatic classification algorithms for identifying images of F-... more This paper deals with developing automatic classification algorithms for identifying images of F-actin distribution in endothelial cells with different treatment of drugs. A novel combination of genetic algorithm based feature selection, used to obtain an optimal feature set, and artificial neural network methods including the multilayer feedforward network and the functional link network was used in the classification. q 1997 Elsevier Science B.V.